Die for forming sheet-metal vessels.



No. 879,922. PATBNTED'FEB. 25, 1908. B. R. STODDARD.

DIE FOR FORMING SHEET METAL VESSELS.

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( 10 I w 3 l I I I I I B Q I 1' I 6 l i I 1,. WITNESSES 2 INVENT'OR Mag?EDGAR RSTOQMRD,

No. 879,922. PATENTED PEB.25,1908. E.R.STODDA-RD.

DIE FOR FORMING SHEET METAL VESSELS.

APPLICATION FILED AUG. 8, 1907. 2 SHEETS-SHEET 2.

v a g! a /i 26 e4- /4' WITNESSES v m d. W47 EDGAR .STODDARD UNITEDSTATES PATENT orrron.

EDGAR R. STODDARD, OF DETROIT, MICHIGAN.

DIE FOIt FOBM ING SHEET METAL VESSELS.

Specification of Letters Patent.

Patented Feb. 26, 1908.

Application filed August 8. 1907. Serial No. 387,580.

To all whom it may concern:

Be it known that I, EDGAR R. STODDARD, a citizen of the United States ofAmerica, residing at Detroit, in the county of Wayne and State ofMichigan, have invented certain ing dies for forming sheet meta bodieswith inclined walls or of variable cross-section,

which are ada ted to exert the necessary pressure upon t e blanks duringthe different i stages of the operation to give permanence and properform to-the finished article.

The invention consists in the matters hereinafter set forth, and moreparticularly pointed out in the appendedclaims.

The articular form of die herein illusbath tubs.

Referring to the drawings, Figure 1 is a trated is adapted for formingsheet metal view in vertical, longitudinal section, of a. d e embodyingthe features of.the invention,

showing the members at the beginning of a stroke; Fig. 2 is a view invertical crosssection on line A.A of Fi 1; Fi 3 is a viewlooking up, online B '0 Fig. 1. F1l;g.(i11is a view in detail of a modified form of te 'e.

A female die 1 whose substantially parallel wall faces 2, perpendicularand face 3 and inclined face 4 have the outer contour of a bath tub, issecured over a corresponding male die 5 which isreciprocated by a head-6 operated by fluid pressure or otherwise suita ly driven in oppositionto a stationary plate 7 which carries the female die, the standards 8that su port the plate affording convenient guides flir the head in theform of ress herein shown.

horizontal clamping plate 9 throughwhich the male die travels, securedto hydraulic plungers 10 or other suitable means,

is adapted to hold the blank against the lower side 11 of the female dieas the male die enters, the bottom of the upper die being A cut :awayand replaced by a foot plate or stripper 12 on a rec ifilfi'locatingplunger 13,

ada ted to eject the- 'shed article.

T e male die 5 consists of .a suitably proportioned stationary section14 secured on the head 6, having side walls 15 and endwall 16corresponding to the faces 2 and 3 of the female die, and a section 17lon 'tudinally movable in ways 18 in the fixe member, constantlyinterlocked fingers 19 on thesections affording practically unbrokenconnections between their working faces. The

movable section 17 has an inclined face, 20 corresponding tothe face fthe female die.

To adapt the die to make several lengths of the same article, as a bathtub, all having the .same ends and width of body, the stationary sectionmay be .two-partwlth fixed central ortion and interchangable ends ofvarious engths, each adapted to be secured thereto by vertical tenons 22and crossins 23, suitable sizes of clamping plates an female dies beingprovided. v I The movable section 17 has a cylindrical chamber 24parallel tothe ways 18, fitted with a plunger or piston 25 whose innerend is secured to the stations. section and whose outer end has a suitabe packing ring or head 26. A supply duct 27 through the piston isconnected by a. feed pipe 28 with suitable pressure tanks oraccumulators 29, suitvalve 31 of any standard design being used toregulate the pressure. A stop-pin 32 engaging a longitudinal slot 39limits the outward movementof the movable section.

In operation, a blank is held against the face of the female die by theclamping plate, and the opened male dle brought against it; the latteris then forced u As the die enters, the perpendicular wa s of thevesselare turned u in the usual manner. The inclined face of t e female dieforms a cam surface down which the correspondin edge of the movable diesection rides over t e inter osed blank, the ressure of the fluid'in thecy der being. regu ated so that the metal is drawn smoothl and heldagainst springing until the fin'a registration of the dies gives apermanent set to that portion of the-metal conable swivel joints 30being provided to 153- mit movement of the head, a contro stituting thesloping side of the tub. The

male die is then retracted through the clamping plate, the foot platefollowing it as an ej ector thatholds the-blank on the receding die.

As the sides of the dies do not exert appreciable lateral pressure, themetal between them is not permanently set, and is liable to s rin in orout when released. To obviate this t e male die is expanded afterwithdrawal by proper manipulation of the controlling valve so that thesides of the tub are stretched taut and smooth beyond the elastic limitof the metal, thus giving them permanent shape.

It is sometimes desirable that the final imression on the bottom of thetub or article he made with a die presenting a solid continuous surfaceand working edge. In such case a modified form of stationary section 33is used, with an upper face 34 and working edge 35 which correspondswith the whole bottom of the article, and a movable section 36 whichslides under and is housed by the stationary; member as. the die isforced home, the oblique face 37 and corresponding edge 38 doing thenecessary work until in register with the other section when the finalpressure 'is exerted.

By using fluid pressure, the operator may accommodate the dies tovarying thicknesses in the blank, and may also increase or decrease theressure at different points of the stroke, as t e circumstances mayrequire.

Obviously, the details of construction and design may be varied withoutde arting from do not care to limit myself-to any particular form orarran ement of parts.

at I claim as m invention is 1. In a device for awing sheet metal, apair of coacting dies adaptedto closejpast each other, one of whichautomatically varies to conform to the others contour as they close,means adapted to close the dies past each other, andmeans to maintainpressure between the variable face of one die and theopposing face ofthe other in directions transverse to the die stroke adapted to actindependently of the die closing means.

2. In a device for drawing sheet metal, a pair of coacting dies adaptedto close ast each other, one of which varies its wor ing face and edgeto conform to the others contour as they close, means adapted to closethe dies past each other and means adapted to maintain ressure betweenthe variable facevof one 1e and the opposing fixed face of the otherdietransversely to the die stroke independently of the die closingmeans.

3. In 'a device for drawing sheet metal, a

pair of coacting dies adapted to close past each other, one of whichvaries to conform to the others contour as they close, and means toforce the variable die and inter osed blank toward the other dietransverse y to the die stroke, and to force the variable die a ainstthe formed blank transversely to the die stroke after both have clearedthe opposing die on the return stroke.

.under pressure adapted to c osethe dies ast 4. In a device for drawingsheet metal, a pair of coacting dies one of which is adapted to vary itsworking face to conform to the others contour when the dies are closedpast.

each other, means adapted to close the dies ace of the variable dieagainst the'opposing die independently of the die closing means, andmeans to vary the ressure exerted by said forcing means at any mstant ofthe stroke.

5. In a device for drawing sheet metal, a pair of coacting dies one ofwhich varies to conform to the others contour as they close past eachother, means 0 erated by fluid each other and means 0 erated .by uidunder pressure adapted to orce the variable die toward the otherdietransversely to the die stroke. I 1 I 6. In a device for drawing sheetmetal, a pair of coacting dies, one of which varies to conform to theothers contour as they close past each other, means 0 erated by fluidunder pressure adapted to orce the variable die toward the other dietransverselyto 1.1163

die stroke, and. fluid pressure controlling means. I

7. In a device for drawing sheet metal,

pair of coactingdies, one of which varies to conform to the otherscontour as they close past each other, means '0 erated by fluid underpressure adapted to orce the variable die toward the other dietransversely to the die stroke and manually operated fluid pressurecontrolling means adapted to vary the pressure at any point of andduring the die stroke. I Y

8. Ina device for drawing sheet metal, a

pair of coacting dies, one of which consists of sections adapted to'varytheirrelative positions transversely to the die stroke to con-, form tothe contour of the other die as the dies close ast each other, and meansoperated by flllld under pressure adapted to force the. sectionsindependently against the opo posin die transverse] to the die stroke. 7

9. a device for r'awing sheet metal, a pair of coacting dies, one ofwhich consists of sections adapted to vary their relative positionstransversely to the die stroke to conform to the contour of the otherdie as the dies close past each other, means operated by fluid underpressure adapted to force the sections independently against the oposing die transversely to the die stroke an manually-operated meansadapted to control and regulate the fluid ressure;

10. In a device or drawing pair of coacting dies, one of which conslstsof sections adapted to vary their relative posi- 5 tions transverselyto' the die stroke to conform to the contour of the otherdie as the diesclose past. each other, a cylinder 1n one section transverse to thep'ath'of the die, a

piston therein secured to an opposing section,

. 70 ast each other, means adapted to force the sheet metal, a

and means to admit fluid under pressure to said cylinder independent ofthe relative po' male die transversely to and independently of the diestroke.

12. In a device for drawing sheet metal, a female die, amale dieconsisting of a fixed section and a yieldable section adapted to followthe contour of the opposing face of the female die as it enters, meansto force the male die bodily into the female die and means adapted toforce the sections of the male die apart transversely to andindependently of the reciprocating means.

13. In a device for drawing sheet metal, a die comprising a fixedsection, a second section movable thereon transversely to the diestroke, a cylindrical chamber in the movable section, a piston thereinsecured to the fixed section, and means to introduce fluid underpressure to said chamber.

14. In a device for drawin sheet metal, a female die having body wal ssubstantially parallel to the die stroke and an end wall obique to the'die stroke, a male die having a fixed section adapted to coact with thebody walls of the female die, and a section interlocking with the fixedsection having a working edge adapted to ride on the end wall of thefemale die as the dies pass each other, a cylinder in one of saidsections and a piston adapted to be 0 erated by fluid under pressure andsecure to the other section, coacting with the cylinder to force themovable section against the oblique end wall transversely to the diestroke.

15. In a device for drawing sheet metal provided with interchan eablefemale dies all having sloping end wal s and similarbody portions ofdifferent lengths, a male die comprising a central fixed sectionprovided with interchangeable end portions adapted to correspond to theseveral body portions of the female dies, and a section movably secured-to expan stroke and retraction, and a manually oper-.

on the central section adapted to yieldingly enga e the S10 ingend wallof any of said fema e dies, an means in the male'die adapted to forcethe movable section against the sloping end wall transversely to andindependently of the die stroke.

16. A machine for formin a sheet metal vessel having a substantia lyrectangular body portion and sloping end walls, comprising a female diehaving end and body walls conforming to the vessel exterior, a clampingplate adapted to hold a blank on the female die, a male die travelingthrough the plate adapted to vary in contour to correspond to the femaledie as it enters, means to force the male die through the plate andfemale die, means to force the clamping plate against the female die andblank as the latter is drawn in by the male die, a foot plate ada ted tocoact with the male die to form the ottom of the vessel and to followsaid die through the female die and clampin .plate on its retraction,and means to expan the male die during and after its stroke andretraction.

17. A machine for formi a sheet metal vessel having a substantia yrectangular body portion and sloping end wall, comprising a emale diehaving end and body walls conforming to the vessel exterior, a clampingplate ada ted to-hold a blank on the female die, a ma e die travelingthrough the plate ada ted to vary incontour to correspond to the emaledie as it enters, means to force the male die through the plate andfemale die, means to force the clam ing plate against the female die andblan as the latter is drawn in by the male die, a foot plate adapted tocoact with the male die on the end of its instroke to form the bottom ofthe vessel and to follow said die through the female die and clam ingplate on its retraction, means (I the male die during and after 1ts atedcontroller and regulator for the expanding means.

11' testimony whereof I aflix my signature. in presence of twowitnesses.

EDGAR R. STODDARD. Witnessesz' C. R. Srroimnv, O'r'ro F. BARTHEL'

